The present invention relates to protective cover for at least one working part of a machine, especially a machine tool.
The working part of the machine moves in a linear direction and the cover is designed to follow the movements of the working part so as to keep the corresponding zone inside the machine protected.
A similar protective cover is known from Italian patent application BO97A 000458 in the name of the same applicant as the present. The protective cover described in that prior application comprises a set of overlapping covering elements in the form of a first covering element that can be fixed to the machine at the zone to be protected, and a plurality of covering elements that move relative to each other and relative to the fixed covering element in the same linear direction as the working part moves. Each covering element also has an opening through which a portion of the working part of the machine can protrude outwards, where the opening in the first covering element forms an area to be covered by the other covering elements, where the covering elements decrease in size to cover corresponding portions of the main opening in the first covering element, and where the mobile covering elements increase in size going from the inside to the outside.
While being advantageous compared to other solutions, the covering elements or plates making up this protective cover are positioned in such a way that when the cover is fitted vertically and the cover plates move up and down along the vertical, following the movements of the working part of the machine, the transversal edges of the plates are positioned horizontally.
Since the plates gradually increase in size going from the inside to the outside, the edges of the plates located below the working part form a series of upward facing horizontal steps. While the machine tool works, the swarf produced by its working part settles on these steps.
In time, the swarf collects on the protective cover and, besides dirtying the cover itself, eventually makes its way into the machine during the sliding movements of the cover plates, thus dirtying and damaging the moving parts of the machine.
The present invention therefore aims to provide a protective cover of the type described above but having covering plates that decrease in size going from the inside to the outside.
With the covering plates fitted in this way and the cover moving vertically, the steps formed by the transversal edges of the covering elements located below the working tool face down, and not up as in the known protective cover. Therefore, the transversal edges of the covering elements located below the working tool do not form a receptacle for the falling swarf as they did in the known protective cover.